MUSSEL FAUNA OF MAUMEE EIVER. 57 



L. rectus was nowhere found in abundance; the examples collected 

 near Defiance were especially large and of fine quality. 



L. ventncosus was nowhere abundant, but was found occasionally 

 all along the river. 



Of exceptionally rare shells, Plagiola securis was represented by 

 only 1 specimen, obtained at the clammer's camp near Fort AVayne. 

 In searching over the pile of shells found in the poultry yard referred 

 to in the early part of this paper, it is believed that an example of 

 Unio crassidens was seen, but as the shell does not appear in our 

 collections its presence in the river can not be predicated with 

 certainty. 



In his paper on " The hydrographic basins of Indiana and their 

 moUuscan fauna," « Dr. Call gives a list of 27 species of Unionidse 

 from the Maumee River; of these, 5 species, viz, Quadnila heros^ 

 Alasmidonta calceola^ Ohovaida retusa^ Ohovaria ellipsis^ and Lamp- 

 silis subrostratus, were not seen by us. 



FOOD OF THE MAUMEE MUSSELS. 



The character of the food of mussels may be better appreciated 

 after a short account of the method of feeding. 



If one looks at a mussel in its natural position in the water one 

 of the first things to attract the attention is two openings, one 

 large and usually conspicuously fringed with elongate papillfe, the 

 other smaller and fringed or not, according to the species. These 

 openings project from the posterior or sharp end of the mussel which 

 is directed upward from the bottom. The larger fringed opening is 

 toward the ventral portion of the mussel and is an incomplete tube 

 formed by portions of the mantle placed together. This is the in- 

 halent opening, and here water is taken into the gill chambers by 

 means of waving cilia which beset the gills, mantle, and other parts 

 of the body bordering on the mantle chamber. The water thus 

 brought in contains oxygen and food particles. The small cilia move 

 the particles up to the anterior end of the body between the large 

 labial palps or lips, which form a sort of funnel to the mouth. Here 

 the food passes through the short g-ullet into the stomach, and thence 

 into a long convoluted alimentary canal, which finally ends at the 

 smaller of the two openings noted above, the exhalent aperture. 



There are minute pores in the gills, and through these the water 

 is forced by cilia into the exhalent aperture, from which it returns 

 to the lake or stream in which the mussel lives. Large robust mus- 

 sels are able to produce quite a strong current, but this is usually not 

 visible in the rippling water where they naturally live. It can be 

 best observed in large river mussels removed from their native stream 



" Proceedings Indiana Academy of Sciences, 1806, pp. 248-257. 



